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mods needed to create torque

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Old Apr 20, 2003 | 05:18 PM
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mods needed to create torque

I just purchased an 88gxl about 3 months ago. I have tried to do as much work on it as posible. So far I had the engine rebuilt, did most of the poly urethane suspension upgrade. Currently I'm working on the suspension.
1. But was just wondering what mods would be suggested to create torque in this engine?
(Would like to keep it N/A if possible.)
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Old Apr 20, 2003 | 05:41 PM
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you are probably going to be hard pressed to find a way of making low-end torque in a rotary. ask around, but theres not much you can do other than to turbo it to make any.
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Old Apr 20, 2003 | 05:58 PM
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not possible to keep it na in that case.
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Old Apr 20, 2003 | 06:06 PM
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even with a turbo anything below 3500 will still bite pretty bad.
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Old Apr 20, 2003 | 06:08 PM
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Old Apr 20, 2003 | 08:20 PM
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V8 swap.


That hurts to say.
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Old Apr 20, 2003 | 08:28 PM
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Im sorry to say, but you should have streetported it when you had the motor apart. Adding a full exhaust system will help out dramatically, and a cold air intake will compliment that nicely.
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Old Apr 20, 2003 | 08:57 PM
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streetporting will help with low end torque? Man, that's a good one. Perhaps wiring your sleeves open will give you more bottom end too?
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Old Apr 20, 2003 | 09:09 PM
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wiring the ports open will kill your low end, they were designed to be closed under 4,000 rpms to help with the low end torque and open after 4,000 to increase air flow and give more high end power
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Old Apr 20, 2003 | 09:09 PM
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streetporting will help with low end torque? Man, that's a good one. Perhaps wiring your sleeves open will give you more bottom end too?
Does your car have a streetport? Mine does and I garuntee it had more low-end torque after the streetport. The low-end might not be as spectacular as the top-end, but it is definately better than with stock ports. By low-end I mean 2500-4500rpm
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Old Apr 20, 2003 | 09:10 PM
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wiring the ports open will kill your low end, they were designed to be closed under 4,000 rpms to help with the low end torque and open after 4,000 to increase air flow and give more high end power
He was joking.
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Old Apr 20, 2003 | 09:13 PM
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Since you are staying NA:
1) Make sure the aux ports (6-ports) are working.
2) Make sure the aux ports (6-ports) are working.
3) Make sure the aux ports (6-ports) are working.
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Old Apr 20, 2003 | 09:14 PM
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Streetporting will produce less low end torque due to the loss in intake velocity.

Best advice is to make sure the 6 port system is working properly (SEARCH!!!)...

If you want to go to extremes, forced induction is always possible. Both superchargers and turbochargers result in basically the same increase in low end, but are not small projects to undertake.

Also switching to a different rear end ratio will make a difference, as well as running smaller tires.
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Old Apr 20, 2003 | 09:14 PM
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Originally posted by BDoty311
The low-end might not be as spectacular as the top-end, but it is definately better than with stock ports. By low-end I mean 2500-4500rpm
That's midrange.

Either way, a small streetport would have little effect on the low end, but if anything it will affect it ADVERSELY. A large street port/bridge port will reduce low end dramatically.

Do I have one? No. But I researched the subject extensively. While the top end gains are incredible, the low rpm range will suffer. I'm sorry if it's hard to accept that, but it's true. Same with backpressure. Low end NEEDS backpressure to help suck the exhaust gasses out... there's a very large subject concerning exhaust pulses and how they help draw out the gasses, but we won't get into that.

Moral of this story, you wont get more low end by street porting your motor. Top end, yes.
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Old Apr 20, 2003 | 09:17 PM
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Right......

Whatever.
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Old Apr 20, 2003 | 09:19 PM
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Since when has changing your gear ratio and tire size increased torque?? And you guys thought my streetport statement was BS.
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Old Apr 20, 2003 | 09:21 PM
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u want to make sure the exhaust piping is not more then 2.5 inches? i can't remember exactly consult mazdatrix for their true dual exhaust system
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Old Apr 20, 2003 | 09:28 PM
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BTW- he asked how to make torque, and a streetport will do that. Maybe not in the low-end 0-2500rpm, but throughout the rest of the powerband it will.
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Old Apr 20, 2003 | 09:49 PM
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Originally posted by BDoty311
Since when has changing your gear ratio and tire size increased torque?? And you guys thought my streetport statement was BS.
Smaller tires/new rear end will result in faster accelleration. Will give the illusion of more torque.

Porting will result in less low end, but better torque higher up.
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Old Apr 21, 2003 | 12:11 AM
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Originally posted by BDoty311
Since when has changing your gear ratio and tire size increased torque??
Only since the invention of the wheel.

Originally posted by Aaron Cake
Smaller tires/new rear end will result in faster accelleration. Will give the illusion of more torque.
The torque increase isn't an illusion, it is real.
http://www.geocities.com/budb3/arts/gear/gfun.html

Originally posted by BDoty311
BTW- he asked how to make torque, and a streetport will do that.
In your defense, he did in fact ask how to create more torque. A streetport will produce more torque in the higher rpm band, which is known as horsepower to the layman. Therefore, you are technically correct.

For those who are not engineering geeks, Horsepower = Torque * rpm / 5252, so you can't have horsepower without torque.

Last edited by Evil Aviator; Apr 21, 2003 at 12:18 AM.
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Old Apr 21, 2003 | 12:26 AM
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I just love it when the knowledged ones lay the smack down with amazing tack

Your the man

James
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Old Apr 21, 2003 | 12:27 AM
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yes but a lot of hp doesn't equal a lot of torque. Just look at the Renesis (250hp, ~150 ft/lbs)
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Old Apr 21, 2003 | 12:48 AM
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Originally posted by Evil Aviator
For those who are not engineering geeks, Horsepower = Torque * rpm / 5252, so you can't have horsepower without torque.
I don't completly understand this.

So say you have 100 hp. At 5,252 RPM then you will have 100 ft/lb.??

So what if you relatively rev it up to 10,504 rpm's, you will have 50 ft/lb??

So does that mean if you keep it at a constant 2,626 rpm you will have 200 lb/ft.??

Please enlighten me.

Tim
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Old Apr 21, 2003 | 01:51 AM
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Originally posted by rotary>piston
yes but a lot of hp doesn't equal a lot of torque. Just look at the Renesis (250hp, ~150 ft/lbs)
Hence the rpm variable in the equation. However, you do bring up an interesting point in that horsepower may also increase with an increase in rpms.

Horsepower is simply torque relative to rpm, and nothing more.

Originally posted by NA_VersionFC3S
So say you have 100 hp. At 5,252 RPM then you will have 100 ft/lb.??
Yes. (Technically it's lbs-ft, said as "pounds feet", even though "foot pounds" is common slang.)

Check out my Miss Cleo bit... With my Evil crystal ball I can see the next dyno sheet that you look at. Go ahead, choose one for any engine you like, just as long as the dyno sheet is in horsepower and lb-ft torque units (not Kw, Ps, or other units). Did you find a dyno sheet yet? OK, now with my amazing Evil powers I will predict that the horsepower and torque curves will meet at exactly 5252rpm. I got it right, didn't I? With my Evil crystal ball I can predict YOUR future by calling 900-EVL-AV8R for only $10/minute. All donations go toward the 20B money pit. The first 10 callers will receive a free bop in the head for not realizing a joke when they see one.

Originally posted by NA_VersionFC3S
So what if you relatively rev it up to 10,504 rpm's, you will have 50 ft/lb??

So does that mean if you keep it at a constant 2,626 rpm you will have 200 lb/ft.??
Yes, but only if the horsepower remains at a constant 100hp, which it will not do in any engine that I know of. You can't use the formula to predict horsepower or torque at different rpms because the engine output will vary. However, if you know two of the three variables, then you can solve for the unknown. For example, Mazda lists the peak torque of an S4 NA 13B at 138 lb-ft @ 3500 rpm. Given this information, our slick forumla shows that the engine will make 92 hp @ 3500 rpm.

Last edited by Evil Aviator; Apr 21, 2003 at 01:53 AM.
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Old Apr 21, 2003 | 02:57 AM
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He prob thought he got more low end torque when he got his engine rebuilt/streetported because his engine was low compression before and since rebuilt it's got more low end torque with a rebuild than before the rebuild.
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